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1.
Epilepsy Behav ; 153: 109716, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508103

RESUMO

OBJECTIVE: This study investigates the prevalence of pathogenic variants in the mechanistic target of rapamycin (mTOR) pathway in surgical specimens of malformations of cortical development (MCDs) and cases with negative histology. The study also aims to evaluate the predictive value of genotype-histotype findings on the surgical outcome. METHODS: The study included patients with drug-resistant focal epilepsy who underwent epilepsy surgery. Cases were selected based on histopathological diagnosis, focusing on MCDs and negative findings. We included brain tissues both as formalin-fixed, paraffin-embedded (FFPE) or fresh frozen (FF) samples. Single-molecule molecular inversion probes (smMIPs) analysis was conducted, targeting the MTOR gene in FFPE samples and 10 genes within the mTOR pathway in FF samples. Correlations between genotype-histotype and surgical outcome were examined. RESULTS: We included 78 patients for whom we obtained 28 FFPE samples and 50 FF tissues. Seventeen pathogenic variants (22 %) were identified and validated, with 13 being somatic within the MTOR gene and 4 germlines (2 DEPDC5, 1 TSC1, 1 TSC2). Pathogenic variants in mTOR pathway genes were exclusively found in FCDII and TSC cases, with a significant association between FCD type IIb and MTOR genotype (P = 0.003). Patients carrying mutations had a slightly better surgical outcome than the overall cohort, however it results not significant. The FCDII diagnosed cases more frequently had normal neuropsychological test, a higher incidence of auras, fewer multiple seizure types, lower occurrence of seizures with awareness impairment, less ictal automatisms, fewer Stereo-EEG investigations, and a longer period long-life of seizure freedom before surgery. SIGNIFICANCE: This study confirms that somatic MTOR variants represent the primary genetic alteration detected in brain specimens from FCDII/TSC cases, while germline DEPDC5, TSC1/TSC2 variants are relatively rare. Systematic screening for these mutations in surgically treated patients' brain specimens can aid histopathological diagnoses and serve as a biomarker for positive surgical outcomes. Certain clinical features associated with pathogenic variants in mTOR pathway genes may suggest a genetic etiology in FCDII patients.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia , Malformações do Desenvolvimento Cortical do Grupo I , Malformações do Desenvolvimento Cortical , Adulto , Humanos , Epilepsia Resistente a Medicamentos/genética , Epilepsia Resistente a Medicamentos/cirurgia , Serina-Treonina Quinases TOR , Epilepsias Parciais/genética , Epilepsias Parciais/diagnóstico , Convulsões , Células Germinativas/patologia , Malformações do Desenvolvimento Cortical/patologia
2.
Seizure ; 85: 115-118, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33453592

RESUMO

Epilepsy with Auditory Features (EAF) is a focal epilepsy syndrome mainly of unknown aetiology. LGI1 and RELN have been identified as the main cause of Autosomal Dominant EAF and anecdotally reported in non-familial cases. Pathogenic variants in SCN1A and DEPDC5 have also been described in a few EAF probands belonging to families with heterogeneous phenotypes and incomplete penetrance. We aimed to estimate the contribution of these genes to the disorder by evaluating the largest cohort of EAF. We included 112 unrelated EAF cases (male/female: 52/60) who underwent genetic analysis by next-generation sequencing (NGS) techniques. Thirty-three (29.5%) were familial cases. We identified a genetic diagnosis for 8% of our cohort, including pathogenic/likely pathogenic variants (4/8 novel) in LGI1 (2.7%, CI: 0.6-7.6); RELN (1.8%; CI: 0.2-6.3); SCN1A (2.7%; CI: 0.6-7.6) and DEPDC5 (0.9%; CI 0-4.9).This study shows that the contribution of each of the known genes to the overall disorder is limited and that the genetic background of EAF is still largely unknown. Our data emphasize the genetic heterogeneity of EAF and will inform the diagnosis and management of individuals with this disorder.


Assuntos
Epilepsia do Lobo Frontal , Síndromes Epilépticas , Feminino , Humanos , Masculino , Mutação , Linhagem , Proteína Reelina
3.
Genet Mol Res ; 16(3)2014 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28829906

RESUMO

ß-glucosidases are enzymes that catalyze the hydrolysis of oligosaccharides and disaccharides, such as cellobiose. These enzymes play a key role in cellulose degrading, such as alleviating product inhibition of cellulases. Consequently, they have been considered essential for the biofuel industry. However, the majority of the characterized ß-glucosidases is inhibited by glucose. Hence, glucose-tolerant ß-glucosidases have been targeted to improve the production of second-generation biofuels. In this paper, we proceeded a systematic literature review (SLR), collected protein structures and constructed a database of glucose-tolerant ß-glucosidases, called betagdb. SLR was performed at PubMed, ScienceDirect and Scopus Library databases and conducted according to PRISMA framework. It was conducted in five steps: i) analysis of duplications, ii) title reading, iii) abstract reading, iv) diagonal reading, and v) full-text reading. The second, third, fourth, and fifth steps were performed independently by two researchers. Besides, we performed bioinformatics analysis on the collected data, such as structural and multiple alignments to detect the most conserved residues in the catalytic pocket, and molecular docking to characterize essential residues for substrate recognizing, glucose tolerance, and the ß-glucosidase activity. We selected 27 papers, 23 sequences, and 5 PDB files of glucose-tolerant ß-glucosidases. We characterized 11 highly conserved residues: H121, W122, N166, E167, N297, Y299, E355, W402, E409, W410, and F418. The presence of these residues may be essential for ß-glucosidases. We also discussed the importance of residues W169, C170, L174, H181, and T226. Furthermore, we proposed that the number of contacts for each residue in the catalytic pocket might be a metric that could be used to suggest mutations. We believe that the herein propositions, together with the sequence and structural data collection, might be helpful for effective engineering of ß-glucosidases for biofuel production and may help to shed some light on the degradation of cellulosic biomass.

4.
J Colloid Interface Sci ; 370(1): 86-93, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22261270

RESUMO

The aggregation properties of 2-, 3-, and 4-fluorobenzoic acids (2FBA, 3FBA, and 4FBA, respectively) and their salts with hexadecyltrimethylammonium cations (HTA2FB, HTA3FB, and HTA4FB) in water were studied with a battery of techniques. Their activity at the air/solution interface has been also studied. The position of the fluorine atom in the acid affected the solubility, adsorption, and aggregation in the pure acids solutions. The 4FBA is less water soluble, more hydrophobic, and has the lower critical aggregation concentration of the three isomers. The behavior of the HTA2FB compound in aqueous solution is different from that of HTA3FB and HTA4FB. The critical micelle concentration, critical concentration for sphere-to-rod-like micelle transition, and Krafft point of HTA3FB and HTA4FB are lower than those of the other surfactant but their surface activities are higher. The differences between the HTA2FB and the other two surfactants have been explained on the basis of the regular solution theory of mixed micelles and in light of the analysis of the hydration shell of the acids through molecular dynamic simulations. The results of the present work suggest that the different behaviors are due to a combination of different dehydration tendencies and the steric possibility of inclusion of the counterions in the micelle palisade layer. The formation of rod-like micelles by HTA2FB, while the tetradecyltrimethylammonium 2-fluorobenzoate only forms spherical aggregates, is explained on the basis of the packing parameter. The mentioned factors are complementary to others presented in literature. These conditions may be used in the rational design of micelles by means of molecular dynamics simulations, reducing the trial-and-error approach used to date.

5.
Bioinformatics ; 28(3): 342-9, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22171332

RESUMO

MOTIVATION: Protein-protein interfaces contain important information about molecular recognition. The discovery of conserved patterns is essential for understanding how substrates and inhibitors are bound and for predicting molecular binding. When an inhibitor binds to different enzymes (e.g. dissimilar sequences, structures or mechanisms what we call cross-inhibition), identification of invariants is a difficult task for which traditional methods may fail. RESULTS: To clarify how cross-inhibition happens, we model the problem, propose and evaluate a methodology called HydroPaCe to detect conserved patterns. Interfaces are modeled as graphs of atomic apolar interactions and hydrophobic patches are computed and summarized by centroids (HP-centroids), and their conservation is detected. Despite sequence and structure dissimilarity, our method achieves an appropriate level of abstraction to obtain invariant properties in cross-inhibition. We show examples in which HP-centroids successfully predicted enzymes that could be inhibited by the studied inhibitors according to BRENDA database. AVAILABILITY: www.dcc.ufmg.br/~raquelcm/hydropace CONTACT: valdetemg@ufmg.br; raquelcm@dcc.ufmg.br; santoro@icb.ufmg.br SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Serina Proteases/química , Serina Proteases/metabolismo , Software , Animais , Interações Hidrofóbicas e Hidrofílicas , Modelos Biológicos , Ovomucina/farmacologia , Proteínas/farmacologia , Perus
6.
Pediátrika (Madr.) ; 20(6): 242-247, jun. 2000. tab
Artigo em Es | IBECS | ID: ibc-12047

RESUMO

La administración de nutrición parenteral total (NPT) se asocia en un porcentaje elevado de pacientes a una alteración de los parámetros indicadores de la función hepática. En estos casos se aconseja retirar la nutrición parenteral e iniciar nutrición enteral lo antes posible. Entre los factores nutricionales que predisponen a colestasis hepática se encuentran: aporte calórico excesivo de lípidos, tipo de mezcla lipídica aportada en la NPT (los de cadena larga LCT mayor que los de cadena corta MCT) y duración de la NPT. En pacientes neonatos, además, la taurina juega un papel muy importante en la prevención y reducción de colestasis asociada con NPT prolongada (AU)


Assuntos
Feminino , Masculino , Humanos , Recém-Nascido , Colestase/diagnóstico , Colestase/terapia , Colestase/etiologia , Fígado/fisiologia , Fígado/fisiopatologia , Fígado/lesões , Recém-Nascido de Baixo Peso , Colestase Intra-Hepática/complicações , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/terapia , Fatores de Risco , Nutrição Enteral/classificação , Nutrição Enteral/métodos , Nutrição Enteral , Gorduras na Dieta/administração & dosagem , Dieta , Síndromes de Malabsorção/complicações , Síndromes de Malabsorção/diagnóstico , Síndromes de Malabsorção/terapia , Taurina/administração & dosagem , Taurina/análise , Taurina/biossíntese , Taurina/metabolismo , Nutrição Parenteral Total/classificação , Nutrição Parenteral Total/métodos , Nutrição Parenteral Total , Nutrição Parenteral Total/efeitos adversos , Nutrição Parenteral Total , Colestase Extra-Hepática/complicações , Colestase Extra-Hepática/diagnóstico , Colestase Extra-Hepática/terapia , Prognóstico , Polissacarídeos/administração & dosagem , Polissacarídeos/uso terapêutico , Monossacarídeos/administração & dosagem , Monossacarídeos/uso terapêutico , Dissacaridases/administração & dosagem , Dissacaridases/uso terapêutico , Ácidos Linoleicos/administração & dosagem , Avaliação Nutricional , Qualidade de Vida , Nutrição Parenteral , Nutrição Parenteral/efeitos adversos , Nutrição Parenteral/métodos , Recém-Nascido de Baixo Peso , Distúrbios Nutricionais/diagnóstico , Distúrbios Nutricionais/dietoterapia , Hepatopatias/dietoterapia , Hepatopatias/reabilitação , Dieta
7.
Boll Soc Ital Biol Sper ; 73(7-8): 107-14, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9796129

RESUMO

The diffusion agar susceptibility test for the antifungal drugs has not been validated yet. The aim of this work has been the analysis of the dose-response line, the relative diffusion rate and the residual activity concerning inhibition zone formation in home-made medium for amphotericin B, 5-flucytosine, fluconazole and itraconazole. Furthermore, the Relative Inhibition Index was calculated. With our methods it is possible to better discriminate the results of "in vitro" antifungal activity above all with those which are less diffused in agar medium.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Antifúngicos/análise , Relação Dose-Resposta a Droga
8.
Farmaco ; 48(12): 1725-33, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8135995

RESUMO

The antimicrobial activity of some pyrido[3',2':4,5]thieno[3,2-d]- 1,2,3-triazine derivatives has been studied. Some compounds proved effective against microorganisms in vitro, compounds 3a and 3c in particular exhibited antifungal activity, comparable to MCZ, against hyphomycetes.


Assuntos
Antifúngicos/síntese química , Triazinas/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Miconazol/farmacologia , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Triazinas/química , Triazinas/farmacologia
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